Answer:
Titan is bigger than Earth's moon, and larger than even the planet Mercury. This mammoth moon is the only moon in the solar system with a dense atmosphere, and it's the only world besides Earth that has standing bodies of liquid, including rivers, lakes and seas, on its surface.
Step-by-step explanation:
Among our solar system's more than 150 known moons, Titan is the only one with a substantial atmosphere. And of all the places in the solar system, Titan is the only place besides Earth known to have liquids in the form of rivers, lakes and seas on its surface.